Direct method of reducing sodium bisuflite affixture of adhehyde or methyl ketone into correspondent alcohol
A technology of sodium bisulfite and addition products, applied in the direction of reduction and preparation of oxygen-containing functional groups, can solve the problems of low yield and decreased purity, and achieve the effects of convenient operation, high purity and high yield
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0013] The preparation of embodiment 1 benzyl alcohol
[0014] Add 15.9g (0.15mol) of sodium carbonate to 60ml of water, then add 4.1g (0.075mol) of potassium borohydride, add 21g (0.1mol) of benzaldehyde in batches at a temperature of 40-50°C for sodium bisulfite addition substance (or its aqueous solution), the reaction is exothermic, after the addition, it is reacted at 40-50°C for 1 hour, cooled, and the lower oil layer is separated, the water phase is extracted with dichloroethane, the oil phase is combined, and the oil phase is washed once with water. Dry over sodium sulfate and concentrate to obtain 9.9 g of benzyl alcohol with a yield of 92%.
[0015] 1 HNMR (300MHz, DMSO-d6) δ7.25-7.43 (m, 5H), 5.35 (t, 1H, J=5.8Hz), 4.62 (d, 2H, J=5.7Hz); MS (m / z, % ), 108 (M+, 100), 91 (16), 79 (89), 51 (16).
Embodiment 2
[0016] Example 2 Preparation of 3,4,5-trifluorobenzyl alcohol
[0017] Add 15.9g (0.15mol) sodium carbonate to 80ml water, then add 2.1g (0.039mol) potassium borohydride, control the temperature at 20-30°C, add dropwise 13.8g (0..05mol) 3,4,5- The solution of the sodium bisulfite adduct of trifluorobenzaldehyde and 70ml of water, the reaction is exothermic, after the addition, it is reacted at 40-50°C for 1 hour, cooled, and the lower oil layer is separated, and the water phase is extracted with dichloroethane. The oil phases were combined, washed once with water, dried over anhydrous sodium sulfate, and concentrated to obtain 7.97 g of 3,4,5-trifluorobenzyl alcohol with a yield of 93%.
[0018] 19 FNMR(282MHz, DMSO-d6)δ+60ppm(2F)+89ppm(1F); 1 HNMR (300MHz, DMSO-d6) δ7.08-7.16 (m, 2H), 5.47 (s, 1H), 4.52 (s, 2H); MS (m / z, %), 175 (M+, 0.45), 162 (100), 145(69), 141(63), 133(59), 113(37).
Embodiment 3
[0019] Example 3 Preparation of 2-fluoro-4-bromobenzyl alcohol
[0020] Add 31.8g (0.3mol) of sodium carbonate to 100ml of water, then add 4.2g (0.078mol) of potassium borohydride, add dropwise 30.6g (0.1mol) of 2-fluoro-4-bromobenzaldehyde at a temperature of 35-40°C The solution of sodium bisulfite adduct and 100ml water, the reaction is exothermic, after the addition, react at 40-50°C for 1 hour, cool, separate the lower oil layer, extract the water phase with dichloroethane, combine the oil phase, The oil phase was washed once with water, dried over anhydrous sodium sulfate, and concentrated to obtain 19.3 g of 2-fluoro-4-bromobenzyl alcohol, with a yield of 95%.
[0021] 19 FNMR (282MHz, DMSO-d6) δ+40ppm; 1 HNMR (300MHz, DMSO-d6) δ7.34-7.45 (m, 3H), 5.38 (t, 1H, J=5.7Hz), 4.52 (s, 2H); MS (m / z, %), 204 (M+ , 78), 189(21), 175(15), 125(100), 107(22), 97(88).
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 